If it were most of the other DBS characters, I would disagree that Cell matters to them. Even a lot of the ToP’s fodder. However, Ribrianne is a different case. See, a lot of people didn’t get this I think: her power isn’t based on ki, it’s based on the amount of love she is taking in and producing. That’s why Base Goku, Super Saiyan Blue Goku, Base Vegeta, Super Saiyan Vegeta, Android 17, and Android 18 can all perform against Ribrianne and get the same results despite the range of power listed is vast. However strong she actually is, it’s mostly meant to be durability. I’m sure Base Goku or Base Vegeta could have actually killed her if the situation didn’t require they be trying to not do that. With all of this in mind, Cell has no reason to lose. He plays for keeps, especially when the opponent doesn’t interest him. Ribrianne can blow him away with however much love she wants, our big bug friend just drinks up all of that delicious zenkai juice. Oh and if Cell uses Self-Destruct, assuming he’s guaranteed a regeneration and didn’t just get lucky during DBZ, we’d need to see evidence Ribrianne can survive in space without oxygen or she’s beyond screwed.

On the one hand, Goku and Vegeta in their BASE FORMS have been shown to be at least on the same tier of power as DBZ-Vegito (Vegeta imposter tanked a double-fisted full power hit to the head from SSJ3 Gotenks without flinching, but Goku fought evenly with him in his base form, and the weakest Z character who might've done that is base form Vegito), and Ribrianne was fighting somewhat evenly with them in their base forms. Cell would likely have been killed by 1-2 of those hits that Ribrianne took. But on the other hand, I never really saw her do that much damage.

BUUUUUUT....In her STRONGEST FORM, she was beaten by #18, who has shown no signs or evidence of being any stronger than she was when she fought Vegeta in Z.